The present invention relates to a flame-retardant carpet and a process for the preparation thereof.
When carpeting is conventionally manufactured, the fibers or pile are tufted on a relatively pliable primary backing which may be manufactured from any suitable materials such as jute or a man-made fiber such as polypropylene. The nonwear side of the backing is then coated with a bonding material of any suitable type such as latex. The latex serves to satisfactorily hold the fibers in place so that they cannot be pulled free from the primary backing and also to bond the primary backing to the secondary backing. In the past, clay has been added to the latex as a filler to reduce the cost of the bonding compound. The secondary backing, which may also be jute or artifical fiber, strengthens the carpet and ensures that the bonding material does not come into contact with the floor upon which the carpet is laid.
U.S. Pat. No. 3,418,267, granted Dec. 24, 1968, relates to flame-resistant polyamides and process thereof. The patent discloses that polyamide resin is made flame-retardant by incorporating therein from 5 to 20 percent by weight of an organic halide, e.g., chlorinated biphenyl, which is reactive with the resin only at its pyrolysis temperature and from 3 to 15 percent by weight of an oxide of tin, lead, copper, iron, zinc, or antimony.
U.S. Pat. No. 3,663,345, granted May 16, 1972, discloses a fire-retardant carpet in which the pile fibers are fixed to the primary backing by a compound comprising a latex binding material combined with an aluminum hydrate.
U.S. Pat. No. 3,719,547, granted Mar. 6, 1973, describes a flame-retardant pile fabric. A fibrous layer composed of combustible filaments or fibers extends from the top surface of a fibrous backing to present a pile surface. A coating of a film-forming halogen-containing polymer and a water-insoluble organo-phosphorus compound is applied to and confined essentially to the top surface of the backing. Where the backing is made of a thermoplastic material, a coating of the halogen-containing polymer may be used without the organo-phosphorus compound.
Although these patents are a major contribution to this art, investigations have been undertaken to produce carpeting that is significantly more flame-retardant than the carpets disclosed in the prior art.